The proposed research is motivated by a new model of age-related declines in cognitive functioning. The model assumes that (a) control over the contents of Working Memory (WM) is central to efficient cognitive processing; (b) such control involves the inhibition of irrelevant streams of thought and (c) because of reduced or sluggish inhibitory mechanisms older adults are less able than younger adults to keep task-unrelated thoughts out of WM. In broad outline, this model is applicable to many areas of cognitive functioning. In this proposal, we hope to both establish the general validity of the model and its usefulness for understanding age-related differences in components of discourse processing. As such, two types of studies are processed: ones focusing on major assumptions of the model (especially the assumption of an age-related decline in the efficiency of inhibitory mechanisms), and ones which apply the model to differences between young and old adults in discourse processing. For the latter, the model suggests that when listening to or reading texts, older adults are hindered by a greater activation into WM, and by a slower removal there from, of thoughts that are not central to the formation of a detailed and integrated representation of the text. These task-irrelevant thoughts compete with task-relevant thoughts in various ways, including, crucially, impeding the retrieval into WM of antecedent and general knowledge information necessary for inference generation and other integrative processes. Repeated experience with retrieval failure may set the stage for the development of compensatory strategies of comprehension. The proposed experiments will use cross- sectional designs to compare the performance of younger (18-30 yrs) and older (63-75 yrs) adults on a variety of experimental paradigms and measures. These will include both direct (e.g., recall and recognition) and indirect (e.g., fragment completion) measures of memory, as well as measures of processing speed. To the extent that the proposed model is confirmed, the findings will, by adding to such concepts as reduced capacity and mental slowing, extend our general understanding of cognitive deficits in aging. Also, to the extent that the results increase our understanding of older adults' limitations in processing discourse, they will have direct application to daily life, especially with respect to the question of how best to present important information (e.g., about health, safety, and legal matters) to older adults.